A. Field of the Invention
The present invention relates generally to slide projectors and more particularly to a selectively positionable slide tray position sensing arrangement that is selectively positionable between two detection positions in response to the type of slide tray positioned on the slide projector as sensed by the position sensing arrangement.
B. Description of the Prior Art
Various control apparatus are known for slide projectors to control positioning of the slide tray to a slide position and the operation of a slide changer to present the slide to a viewing position. These various control apparatus are conrollable in either a manual mode or a random access mode. Arrangements of this type, for example, are disclosed in U.S. Pat. Nos. 3,296,727, 3,225,652, 3,299,554, 3,895,864, 3,907,414, 3,924,942, 3,566,370, 4,041,457, 3,510,215, 3,644,027, 3,733,122, 3,652,155, 3,623,803, 3,700,320 and 3,732,546.
While the above described control apparatus of the prior art are generally suitable for their intended use, it would be desirable to more accurately control slide tray positioning and to provide a slide tray position sensing arrangement that is selectively positionable between two detection positions for appropriate alignment and detection of the slide positions of two tray types having a different number of slide positions.